A display server to drive ws281x led strips on an ambeded ARM computer

It acepts a stream of unsigned ints

Author: Bruno Laurencich (https://github.com/daylanKifky)

Based on the Python wrapper for the rpi_ws281x library. Author: Tony DiCola (tony@tonydicola.com)

Based on rpi_ws281x library by Jeremy Garff Copyright (c) 2014 Jeremy Garff <jer @ jers.net>

Installation:

Make sure you have scons and swig installed, or (on a debian based system)

sudo apt install scons swig python-dev

Then, you need to get the base library from https://github.com/jgarff/rpi_ws281x, and build it inside /lib

cd lib
git clone https://github.com/jgarff/rpi_ws281x
cd rpi_ws281x

• Make sure to adjust the parameters in main.c to suit your hardare.
  • Signal rate (400kHz to 800kHz). Default 800kHz.
  • ledstring.invert=1 if using a inverting level shifter.
  • Width and height of LED matrix (height=1 for LED string).

Build it

scons

Now, you have to build the python wrapper

cd python
python ./setup.py build

If you are rebuilding after fetching some updated commits, you might need to remove the build directory first

rm -rf ./build

Usage:

instructions to test it on a Raspberry Pi 3

• Power your led strip and connect the data pin to your GPIO pin 18. If you wish you can configure the GPIO pin and other parameters inside ws_2811_conf.py.

• Run the display server with administrator privileges:

sudo python display_server.py

• Send a test message to the display server:

sudo python socket_send_test.py

(you should see a blue gradient on the leds)

• Now you can send messages the UNIX socket: /tmp/display-server-socket, with the format: '<IIIIIIIIIIIIIIII' where each of the integers correspond to the 32bits rgb value of each led on a 16 leds strip.

The server can also be initialized to manage a different amount of leds:

sudo python display_server.py -b [NUMBER_OF_LEDS]

or to use a different Socket file:

sudo python display_server.py -s [PATH_TO_SOCKET]